1. Field of the Invention
The invention relates to a vortex flowmeter having a measuring tube, a housing, a bluff body (i.e., A body having a broad, flattened front) and a sensor unit, wherein the sensor unit serves to detect a vortex measuring signal caused by the bluff body. Furthermore, the invention relates to a method for operating a vortex flowmeter having a sensor unit and at last one inertial sensor.
2. Description of Related Art
Vortex flowmeter have been known for a long time, wherein the measurement principle is based on the fact that a vortex street can be formed in a liquid or gaseous medium behind a bluff body that the medium flows around, the vortex street being formed by the vortex moving with the flow, displaced by the bluff body. The frequency, with which the vortex is displaced by the bluff body, is dependent on the flow rate, wherein this correlation is nearly linear under certain circumstances. At any rate, the measurement of the vortex frequency represents a suitable means for determining the flow rate of the medium, which is indirectly why—under additional consideration of, for example, pressure and temperature—a determination of the measuring flow is possible using the vortex frequency measurement. The vortex of the medium occurring in a vortex street leads to local pressure fluctuations, which can be detected by the sensor unit—usually a pressure sensor.
Since the determination of the flow rate in vortex flowmeters is based on the measurement of pressure fluctuations, the vortex flowmeter is sensitive to vibrations in the complete system, which can, thus, influence the quality of the measurement results.